The dominant practice nowadays is to bale hay in large cylindrical rolls, instead of small rectangular bales, the hay being bound by several circumscribing lengths of twine or similar cord. Balers pick up the hay, roll it up tightly, bind it, and then discharge it back onto the ground. Typically, whether left there or moved elsewhere, the bales always reside on their peripheral side, not on their ends. The tight binding of the hay on the periphery of the bales is supposed to protect them from deterioration when left out in the weather. But that is usually not the case, especially when the bales are left exposed for any length of time, as over the winter.
To protect the bales over long periods of exposure, large "tubes" of plastic sheet material are marketed. Each bale is raised by fork lifts stuck into one end and a "tube" manually slipped over its periphery. These "tubes", however, are expensive, do not always protect the bales sufficiently, and are difficult to apply. Another approach is embodied in devices designed to wrap the bales with plastic sheet material fed from a roll as the bale is revolved about a horizontal axis. See, for example, U.S. Pat. Nos. 4,173,112 and 4,296,595. Often these devices are incorporated into the balers themselves. But balers so equipped have proved troublesome in practice, often imperfectly wrapping the bales, breaking the sheet material, and the like. Since the wrapping mechanism is housed within the baler, breaks in the material, imperfectly wrapped bales, and so forth, are not easily or quickly corrected. Even in instances in which such devices are separate machines, apart from the balers, problems persist. Picking up a bale in the field, holding it while it is rotated about a horizontal axis and wrapped, has, so far as known, not been successfully accomplished from a practical standpoint. Hence, the chief object of the present invention is an improved bale wrapping machine in which the wrapping material is fed from a roll while the bale is rotated.